<div id="app">
    <div @click="change">666aaaa{{ test.name }}</div>
    <fncomp :vnode="vnode"></fncomp>
 </div>
<script>
  const vm = new Vue({
    el: '#app',
    data: {
      test: {
        name: 12,
        age: 20,
        arr: [1, {a: 'a'}]
      },
      vnode: 123
    },
    components: {
      fncomp: {
        functional: true, // 函數(shù)式組件
        render(h, ctx) {
          return ctx.props.vnode
        }
      }
    },
    methods: {
      change() {
        console.log(this._vnode)
        this.vnode = this._vnode.children[0]
      }
    },
    computed: {
      fullTest({ test }) {
        return test.name + test.age
      }
    },
    watch: {
      // 要監(jiān)聽2個(gè)值有沒有變化可以在 computed 里定義一個(gè)變量 這里做監(jiān)聽
      fullTest(val) {
        console.log(val)
      }
    }
  })
  console.log(vm)
</script>